An empire cannot be created by a republic

From Tony Judt’s “The New World Order” (The New York Review of Books: 14 July 2005):

Historians and pundits who leap aboard the bandwagon of American Empire have forgotten a little too quickly that for an empire to be born, a republic has first to die. In the longer run no country can expect to behave imperially – brutally, contemptuously, illegally – abroad while preserving republican values at home. For it is a mistake to suppose that institutions alone will save a republic from the abuses of power to which empire inevitably leads. It is not institutions that make or break republics, it is men. And in the United States today, the men (and women) of the country’s political class have failed. Congress appears helpless to impede the concentration of power in the executive branch; indeed, with few exceptions it has contributed actively and even enthusiastically to the process.